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Old 21st October 2014, 12:47   #16
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Re: Thar CRDe: Improving its low-end torque

The below upgrades will fix your problem;
1. Pop a Race Dynamics Dieseltronics dual channel ecm and add a K&N stock replacement filter.
2. Increase your average tyre pressure by a couple of psi's
3. Get a custom turbo down pipe, the OEM ones are generally restrictive, this restriction slows the exhaust gas exit speed disallowing for faster turbo spooling when needed.

I have done the above in my chevy cruze as in stock state it suffers from a similar issue, now the driveability has improved across the revv range by a hugh margin. Its just a much better car to drive now.

Note: Do not tamper with axle ratio or gears, not worth the hazzle. If the above mods are not sufficient, move to light weight alloys, lesser unsprung weight makes a lot of difference at the low end of the power band due to a lesser coefficient of drag and minimized rotational force needed to drive the wheels.

Last edited by The Wolf : 21st October 2014 at 12:52.
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Old 21st October 2014, 14:47   #17
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Re: Thar CRDe: Improving its low-end torque

I am reading all of your responses very carefully, thanks all.

B.D. has suggested in the past that I could plonk a 2.6L into the Thar and then have something approaching his intent for this vehicle ala his much beloved test bed. I would do this in a heart beat if there was a trusted shop that I knew of here in Northern India.
And, where in the world do I get a 2.6L that I know is in "like new" condition?

I am not a hard core off roader and I chose Thar CRDe largely for trekking the Himalayas, "bad-roading" as opposed to off-roading. I wanted the CRDe drivetrain and engine, or so I thought at the time. But the accursed thing does not go up hills worth spit!

I considered Thar Di. But especially after reading 4x4Addict's wrestling match with his Thar Di, I went with the CRDe. I want to avoid the Di's hassles, though I still might buy one. I am so disenchanted with M&M and their notions of parts and service that I would really not want to buy one of their vehicles in the future unless there were new advantages to my 'parts and services" situation.

See 4x4Addict's fine thread http://www.team-bhp.com/forum/4x4-ve...i-finally.html

It is my good fortune to be able to buy another CRDe or a Di or maybe a Bolero Camper for trekking. I am hoping something more suitable breaks into the market for early 2015, something not Mahindra, something not Tata either.

By the way, you guys might want to see the comments made by Ringoism in his thread

http://www.team-bhp.com/forum/4x4-ve...aul-spiti.html

It seems that M&M has lost sight of the fact that there are hills in India. Gee, what a surprise, hills! Oh, and yes, Mahindra, there are also monsoons. Windshield wipers cannot yet be deleted from your vehicles as a cost savings vector for your customers. But try it, try selling cars without wipers and see if anybody complains.
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Old 21st October 2014, 15:03   #18
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Re: Thar CRDe: Improving its low-end torque

Quote:
Originally Posted by KMT View Post
The guys who changed the 2.6 engine to a 2.5 screwed up by making the engine oversquare. Who puts an oversquare engine in an off roader? Oh I forgot its the geniuses at M&M.
Dear Ken / KMT / all - don't monkey around with chips and clips, you will lose power, reliability and money. .

I think you will still remember a vehicle known as MH01V521. The correct solution was there inside it, every single thing. Ken, you should have driven MH01V521 up Himalayan slopes where you stay, then you would tell a different story. On the open expressways, I used to just ccrruuiizzee. A torpedo, that's what it was!

By the way, the rpm of the engine will not reduce suddenly when you leave the accelerator, thanks to BS4 in which HC and NOx have to be critically controlled to pass the test on the chassis dynamometer in V1. .

I can see that you are looking for "something". Let's see now, there is a very big island somewhere in the southern hemisphere -----!

Best regards,

Behram Dhabhar

Last edited by Samurai : 21st October 2014 at 16:43. Reason: avoid highspeed reference
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Old 21st October 2014, 16:07   #19
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Re: Thar CRDe: Improving its low-end torque

Quote:
Originally Posted by DHABHAR.BEHRAM View Post
Dear Ken / KMT / all - don't monkey around with chips and clips, you will lose power, reliability and money. .
Behram baba...I would like to politely disagree with you on this. There are products that are personally used and recommended by thousands that are also rally, drag and track tested available to us today for a few thousands. The reliability of these products is well proven. Coming to 'lose power', we can but dynamometers dont lie. Lastly, I have not known of a single case of engine failure due to the usage of an after market ecm of a reputed brand.

Quote:
Originally Posted by DHABHAR.BEHRAM View Post
I think you will still remember a vehicle known as MH01V521. The correct solution was there inside it, every single thing. Ken, you should have driven MH01V521 up Himalayan slopes where you stay, then you would tell a different story. On the open expressways, I used to just ccrruuiizzee. A torpedo, that's what it was!
So you are recommending tampering with axle ratios and local mechanics, on brand new and old scorpios??? Tell me what I need to smoke to understand you better babaji :P

Quote:
Originally Posted by DHABHAR.BEHRAM View Post
By the way, the rpm of the engine will not reduce suddenly when you leave the accelerator, thanks to BS4 in which HC and NOx have to be critically controlled to pass the test on the chassis dynamometer in V1. .
Yeah, heard that before. Not sure what percentage of that is controllable through better engineering though.

Quote:
Originally Posted by DHABHAR.BEHRAM View Post
I can see that you are looking for "something". Let's see now, there is a very big island somewhere in the southern hemisphere -----!
Will park this for now

Last edited by Samurai : 21st October 2014 at 16:43. Reason: removed highspeed reference from quoted text
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Old 21st October 2014, 17:53   #20
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Re: Thar CRDe: Improving its low-end torque

Quote:
Originally Posted by desertfox View Post
For short drives on the hill say 15 to 20 min the problem can be solved by engaging in 4th gear Low ratio.

However long periods of driving on sealed tarmac with 4WD Low engaged will cause problems its not sand under the wheels.
This made me think. Because I have manually-lockable hubs on my Jeep, I can switch the transfer case to 'low', while still continuing on in 4x2.

Guess this isn't an option with the Thar. Low ratio is possible in 4x4 only.

@ DirtyDan, did you finally install the free-wheeling hubs (thread link)? If so, why not disengage the front, and use 3rd low in 2WD mode? You can go higher / lower as per the requirement

Quote:
Originally Posted by The Wolf View Post
Increase your average tyre pressure by a couple of psi's
Didn't understand the benefit of this, Wolf? How would tyre pressure help here?
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Old 21st October 2014, 18:29   #21
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Re: Thar CRDe: Improving its low-end torque

Hi Dan

Check out the on/off/hilly road behavior of the Scorpio CRDe 4x4 (older vehicle . Not the VLX version), considering that the Thar CRDe is nothing but a Scorpio under an MM5xx body shell.

If you find the Scorpio's low end torque better, I guess you can try flashing your ECU with the Scorp's program.

Just my 2 paise.
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Old 21st October 2014, 19:21   #22
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Re: Thar CRDe: Improving its low-end torque

Quote:
Originally Posted by DHABHAR.BEHRAM View Post
[b][u]

I can see that you are looking for "something". Let's see now, there is a very big island somewhere in the southern hemisphere -----!

Best regards,

Behram Dhabhar
Quote:
Originally Posted by GTO View Post
.

@ DirtyDan, did you finally install the free-wheeling hubs (thread link)? If so, why not disengage the front, and use 3rd low in 2WD mode? You can go higher / lower as per the requirement
Anybody know if Australia is a big island or a continent?
Anybody know the tele number of any Mahindra diesel shops in Madagascar?

GTO, too much chance of snapping the rear axle by using LOW range in this way. I am not sure how much is too much in this case and I don't really want to find out. I had a mechanic work and rework my T-case and T-case lever. That seems to have helped my engage/disengage problem for the time being.
I have not added aftermarket hubs.

A Maruti Jimny might cure this whole business. C'mon Maruti, get with the program. Where is your answer to Duster and Thar?
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Old 21st October 2014, 20:17   #23
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Re: Thar CRDe: Improving its low-end torque

Quote:
Originally Posted by KMT View Post
Sutripta
Are you suggesting a lower second gear or a lower diff ratio.
Yes.
As an experiment, one could fit smaller wheels mimicing the required final drive ratio to see if it helps.

Quote:
Is it possible to lower 2nd gear?
If you have access to the whole bag of tricks, or can make your own, yes!
Actual answer (In our context) - No.

Regards
Sutripta
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Old 21st October 2014, 20:28   #24
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Re: Thar CRDe: Improving its low-end torque

Quote:
Originally Posted by GTO View Post
Didn't understand the benefit of this, Wolf? How would tyre pressure help here?
This ones a simple trick that seems to work, whenever the vehicle is begging for every ounce of torque needed to move it increasing the tyre pressure by a few psi makes that little positive difference by reducing the rolling resistance. This particularly works on vehicles with large radial tyres as the contact area is significant enough to slow down the vehicle due to the corresponding coefficient of drag it creates. Lets say you generally run your diesel SUV's tyres at 28psi, try to take it up a steep incline (solid surface only) by moving the vehicle in 2nd or 3rd gear at idle. Then change the tyre pressure to 32-33psi and try the same, you will be surprised with the difference observed. The vehicle will suddenly seem like its magically gained an invisible 20nm

Last edited by The Wolf : 21st October 2014 at 20:29.
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Old 21st October 2014, 21:20   #25
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Re: Thar CRDe: Improving its low-end torque

The only thing you can do at lower cost is go for 15" tires. You wil lose around 20mm of GC, and gain about 10% extra torque.
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Old 21st October 2014, 21:35   #26
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Re: Thar CRDe: Improving its low-end torque

I follow Wolf's logic of reducing rolling resistance. And I have experimented a bit with it. But there are also potholes the size of moon craters on Himachal roads and the Thar already does not ride well over them at normal inflation. I don't want to turn it into a lumber wagon. My Invader rides better, in fact. So why don't I use my Invader? Hard to steer, a plethora of niggling problems as well. No heater, no a/c. Right now a rear axle seal is leaking diff gear oil, have to get that fixed. And so it goes.

I follow Sutripta's logic of using smaller wheels.

My instinct is that these taken together will not come close to giving me enough power to make up the deposit. B.D.s solution of going to a 2.6L will inject the massive increase in torque that is needed in this case.

Would you believe, Jeep in North America used to offer 5.0L V8 motors, 200 hp, in similar jeeps and also large 6 cylinder motors in the 1970s and 1980s/. No problems with torque for sure. Lots of problems with tipping but no problems with torque.
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Old 21st October 2014, 22:15   #27
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Re: Thar CRDe: Improving its low-end torque

Quote:
Originally Posted by DirtyDan View Post
Anybody know if Australia is a big island or a continent?
there is no universally accepted/agreed definition for what constitutes an island or a continent. But the general consensus seems to be that Australia should be called a continent, based on its size.

http://geography.about.com/od/learna...continents.htm

Jeroen
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Old 21st October 2014, 23:02   #28
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Re: Thar CRDe: Improving its low-end torque

Quote:
Originally Posted by DirtyDan View Post
I follow Wolf's logic of reducing rolling resistance. And I have experimented a bit with it. But there are also potholes the size of moon craters on Himachal roads and the Thar already does not ride well over them at normal inflation. I don't want to turn it into a lumber wagon. My Invader rides better, in fact. So why don't I use my Invader? Hard to steer, a plethora of niggling problems as well. No heater, no a/c. Right now a rear axle seal is leaking diff gear oil, have to get that fixed. And so it goes.

I follow Sutripta's logic of using smaller wheels.

My instinct is that these taken together will not come close to giving me enough power to make up the deposit. B.D.s solution of going to a 2.6L will inject the massive increase in torque that is needed in this case.

Would you believe, Jeep in North America used to offer 5.0L V8 motors, 200 hp, in similar jeeps and also large 6 cylinder motors in the 1970s and 1980s/. No problems with torque for sure. Lots of problems with tipping but no problems with torque.
Bro, I can see that you have covered most ground already. Only logical thing is an ecm, try to request for a demo piece through a local RaceDynamics dealer, plug it and use it.....if its use seems logical beyond other mods keep it or return it. If none works...go and book a Duster AWD

Regarding australia being a continent or a large island, well it is a continent as it sits on tectonic plates unlike an island. So much for our seach for the magical solution on the southern hemisphere which also contains a bit of asia, africa, s.america and antarctica, well... this is going to take some time
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Old 22nd October 2014, 09:52   #29
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Re: Thar CRDe: Improving its low-end torque

I agree that mahindra lost the plot on the 2.5 compared to the 2.6

With an engine that was designed for the xylo with its 26" puny tyres, I guess anemia is to be expected

On my 2.6 scorp, I am running a remap from code6 with the EGR deleted... Hills that needed a 2000 rpm start are idle starts..
I was running the race dynamics box earlier.

I have a couple of friends running the box on thars .
works well

try it.. Very roll backable mod.
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Old 22nd October 2014, 16:50   #30
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Re: Thar CRDe: Improving its low-end torque

Not sure if someone mentioned earlier but the DieselTronics box for Thar has a special "off-road" tune which provides better lower-end, or so they claim. Would recommend looking it up.
Link


Quote:
Originally Posted by Sutripta View Post
Yes.
As an experiment, one could fit smaller wheels mimicing the required final drive ratio to see if it helps.
OT: Your suggestion if possible in the KMT-90 would be great for the 4th gear (from1:1 to 0.75:1) but it's off-topic here. Would love to know though if its possible.

Quote:
Originally Posted by tsk1979 View Post
The only thing you can do at lower cost is go for 15" tires. You wil lose around 20mm of GC, and gain about 10% extra torque.
I think that would depend on the overall dia of the tyre (29/30/31") and not the size of the rim (15")

Last edited by AVR : 22nd October 2014 at 16:55. Reason: Added quote
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